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Predators In The St. Lawrence: Navy, Part 50

Survivors of USS Chatham are taken on board HMCS Trail, August 1942. [PHOTO: LIBRARY AND ARCHIVES CANADA—PA200327]

Survivors of USS Chatham are taken on board HMCS Trail, August 1942.

The attacks on Nicoya and Leto on May 12, 1942, signalled the commencement of what became known as the Battle of the St. Lawrence, the most important enemy intrusion into Canadian territory—and the Canadian psyche—of the war. Although the threat was continuous throughout the shipping season and 22 vessels were lost in the river and gulf in 1942, the battle divides into three distinct phases. The first was the cruise of U-553 and the first sinkings on May 12 (The Battle Of The St. Lawrence Begins, January/February). In early July, U-132 arrived and sank five vessels over several weeks, marking the first attacks against organized and escorted convoys in the area. But the heaviest and most dramatic events took place in late summer when a tandem of skilled and aggressive submariners did enough damage to force the RCN to close the gulf and river to oceanic shipping. That devastating third phase had its origins in the tail end of the U-132’s cruise, and it brought the war to the most remote region of the gulf: the Strait of Belle Isle.

As discussed in the previous column, U-132 commanded by Kapitänleutnant Ernst Vogelsang, attacked convoy QS-15 near Rimouski, Que., on July 6, and nearly escaped destruction by the Bangor-class escort Drummondville. After firing her torpedoes, U-132 was briefly trapped in the surface layer of fresh water, unable to push into the dense, cold seawater that lay 60 metres down. The hasty attack by Drummondville therefore found U-132 close to the surface, and bracketed it with three well-placed depth charges. The sub was damaged by the blasts, especially her main ballast pump. Vogelsang punched U-132 down into the colder seawater by flooding his forward torpedo tubes, which turned the U-boat into a stone. U-132 descended to 184 metres before her plunge was checked by blowing ballast. The last of Drummondville’s depth charges were heard as U-132 stabilized at 100 metres. It was a very close run thing. Had Drummondville’s attack destroyed U-132, 1942 might have gone much differently for both the RCN and for the Canadian government. But not for the last time a U-boat escaped destruction in the Gulf of St. Lawrence by the narrowest of margins.

Evidence of a torpedo hit on SS Frederika, July 1942. [PHOTO: NAVAL MUSEUM OF QUEBEC]

Evidence of a torpedo hit on SS Frederika, July 1942.

Following the attack on July 6, Vogelsang took U-132 to the quiet waters of the northern gulf to affect repairs and to report on traffic using the Strait of Belle Isle. Few ships seemed to be using the strait, he reported, and operational conditions were “unfavourable,” U-boat headquarters was not so sure, and believed that the strait was being used by oceanic convoys to avoid U-boat packs on the Grand Banks. Nothing Vogelsang reported dissuaded them of this belief.

While higher authorities pondered the issue, by July 20, U-132 was back hunting off Cap de la Madeleine, Gaspe. Air patrols—the only effective deterrent in the gulf in 1942—kept Vogelsang at bay for several days and prevented him from gaining an attack position on two steamers on the 19th. His luck changed the next day, when the convoy QS-19 was sighted through the periscope. None of the escorts—the corvette Weyburn out ahead, the Bangor Chedabucto on the portside or the three Fairmile Motor Launches on the landward side and astern—saw the tiny attack periscope of U-132. Vogelsang fired two torpedoes, one of which struck the 4,367-ton British freighter Frederika Lensen, travelling in ballast from Montreal to Sydney. The explosion in the engine room killed four crew and broke the ship’s back.

The escort responded immediately, but without effect. One of the Motor Launches on the starboard side of the convoy, where the Frederika Lensen was now stopped, attacked a contact. According to the RCN’s official history, this was later rated as a school of fish because the depth charges simply “brought a larger number of dead herring to the surface.” Certainly, Vogelsang and his crew felt none of the charges. Air coverage of the scene kept U-132 submerged and prevented further attacks on the crippled steamer as HMCS Weyburn towed it safely to Grande Vallee, Que. There the Frederika Lensen was beached and declared a total loss. Forty-two of the crew were saved. No retribution was extracted from U-132, which then turned for home and arrived back in France in mid-August.

The quiet—in the gulf if not in Parliament and the press—lasted for about a month. Based in part on Vogelsang’s report that there was traffic passing through the Strait of Belle Isle, the Germans dispatched three large, type IX U-boats to the area. They would constitute the heaviest assault on shipping in Canadian waters during the war, and their success would deeply embarrass the navy and the government. U-513 under Korvettenkapitän Rolf Ruggeberg was assigned to patrol outside the Strait of Belle Isle. He never did enter the gulf, but we will meet up with him again.

The first to pass through, U-517, commanded by Kapitänleutnant Paul Hartwig, entered the strait in the early hours of Aug. 27 and it is likely that U-165 (sunk on her way home) under Korvettenkapitän Eberhard Hoffmann arrived about the same time.

Hartwig reported that his passage of the strait on the surface, three miles offshore and using local navigation lights, was “no problem.” Finding targets proved remarkably easy, too. By August the narrow passage between the Great Northern Peninsula of Newfoundland and the Labrador coast was busy with traffic, much of it destined for the new American airbases across the Arctic. So, despite the “unfavourable” judgement of Vogelsang, his senior officers had guessed right: the convoys—local, not transatlantic—were there.


HMCS Weyburn.

When Hartwig submerged at daylight to patrol the southern entrance to the strait, the RCN history observed, “no fewer than three groups of ships were approaching the strait from the south.” The first was the “fast group” of the U.S. convoy SG-6, which had sailed from Sydney on Aug. 25 for Greenland. This section consisted to the U.S. Coast Guard cutter Mojave escorting the troop transport Chatham with 428 U.S. and Canadian labourers aboard. Some hours behind the fast group was the lumbering main body of SG-6: three merchant vessels, plus the U.S. Navy oiler Laramie and an aging coal-burning USN auxiliary ship, the USS Harjurand, which was capable of only seven knots, screened two other USCG vessels, Algonquin and Mohawk. As the USN official history commented, this division of SG-6 only succeeded in making both parts weak.

Wedged in between the two sections of SG-6 was a small Canadian convoy, NL-6, of two merchant ships escorted by the corvette Trail, en route from Quebec to Goose Bay. Quite fortuitously then, Hartwig had submerged right into the path of seven merchant vessels: the targets came to him.

There is no indication that the escorts were aware that U-boats were in the strait. SG-6 had no air cover that morning, but a Douglas Digby from 10 Squadron, Royal Canadian Air Force, was in support of NL-6 in between the two American sections. That aircraft was 25 miles south of the fast section of the American convoy when, at 8:48 a.m., a torpedo exploded in Chatham’s boiler room. A second explosion quickly followed when the chilled seawater detonated her boilers.

It took Chatham a half hour to sink, and virtually all of her passengers and crew escaped into boats. As it turned out, Hartwig was in no position to deliver a final blow. In the complex mixture of the local waters, the act of firing the torpedoes had sent U-517 into a descent, and Hartwig was content to lay low for 40 minutes anyway before popping up for a look through his periscope. By then, Chatham was gone. As Mojave searched the area for U-517, support arrived from the south, first in the form of the RCAF Digby, and then USCG cutter Mohawk. HMCS Trail was actually closer to the scene than Mohawk or Algonquin, but she prudently escorted her little convoy into Forteau Bay on the Labrador coast before joining the search in the early afternoon. By late afternoon, when Trail returned to Forteau Bay with 88 survivors on board, an RCAF Catalina from 116 Sqdn. at Dartmouth, N.S., was flying over the area of the attack.

Hartwig feared needlessly that he would be discovered by the escorts’ searching asdics. The captain of Trail, Lieut.(N) G.S. Hall, RCNR, reported later (as quoted in the RCN official history) “Asdic conditions were bad, non-sub contacts could be obtained all around the ship on the riptides and water temperature gradients, and it was obvious that the effectiveness of an A/S screen would be greatly affected in this part of the strait.” In fact, local currents were strong enough to allow U-517 to clear the area of the attack with little use of her motors: she would be back.

Sadly, none of the U.S. Coast Guard cutters reported the attack to the American admiral in charge of convoy operations in the northwest Atlantic, Commander Task-Force 24 in Argentia, Nfld. Nor is there any suggestion in existing accounts that Trail did, although the RCAF responded by dispatching a Catalina. Clearly there was a major mixup in proper reporting. It is true that the action was too far away for quick naval reinforcement, but the rest of SG-6 might have been diverted into Forteau Bay, where NL-6 lay. Instead, SG-6’s slow section plodded northward into the danger area screened only by the cutter Algonquin.

Since U-165 did not survive her patrol, we have no clear idea of when she entered the Strait of Belle Isle or precisely what Hoffmann saw and did. However, we do know that very late on Aug. 27 he stumbled on SG-6. At 9:30 p.m. local time, U-165 fired a spread of four torpedoes at the SS Alyn, a 3,304-ton U.S. registered ship carrying dynamite, high test fuel and other cargo. Two struck, the third and fourth missed. Fearful of an explosion, Alyn’s crew abandoned ship quickly, and were later picked up by Harjurand. Down by the stern, Alyn stayed afloat and her coast guard guns crew stayed at its posts until Hartwig—hunting once again—found her hours later and sent her to the bottom.

U-517 dives to avoid aerial attack on the St. Lawrence, 1942. [PHOTO: CANADIAN FORCES JOINT IMAGERY CENTRE]

U-517 dives to avoid aerial attack on the St. Lawrence, 1942.

U-165’s fourth torpedo ran a little further and hit the USN oiler Laramie. She was filled with volatile aviation gas and ought to have gone up like a bomb. The torpedo blew a hole 40-feet wide and 35-feet high in her side, burst the port gasoline tank and sprayed the whole ship with fuel. Miraculously, no fire broke out. The Americans fought to save her despite the prospect of imminent immolation; the guns crew commented later that they were often ankle deep in gasoline. Pyrotechnics and tracer lit the night sky, but no U-boat was ever seen. Laramie was saved by her gallant crew and returned to Sydney without further incident.

In the grand scheme of things, the loss of two ships and damage to a third was not a great event in the war, although Chatham was the first American troopship sunk by enemy action. At best, the events of Aug. 27 were high drama in an otherwise quiet and remote theatre. And more drama was on the way. On Aug. 28, Hartwig was hunting in the Labrador Sea, where he had a brief encounter with a Canadian patrol. On Sept. 1, he was back in the Strait of Belle Isle and, in a bold move, entered Forteau Bay at night, on the surface, approaching to within 20 metres of the wharf undetected. As he was leaving, HMCS Weyburn steamed past U-517 in the dark, close enough for the two vessels deck watches to see one another. As Weyburn spun around, Hartwig sent his U-boat down in a crash dive and later expressed his astonishment that the Canadian corvette was so poor at anti-submarine warfare that it never attacked him. As the Canadian records reveal, that was not for want of trying: asdic conditions were just so bad that Weyburn’s searching beam never found the sub.

Weyburn got another chance at Hartwig several days later, and had no better luck. The corvette and her sister Shawinigan were escorting a three-ship NL convoy along the Labrador coast on Sept. 2. Hartwig had lined up for the nighttime shot on the surface, and had just fired a salvo when, as historian Michael Hadley recounted, Hartwig saw “an escort turning hard about and running toward” him. U-517, faster on the surface than a corvette, went to full but Weyburn was too close. When Lieutenant-Commander T.M.W. Goldby, RCNR, ordered his four-inch gun to fire, U-517 crash dived. Nothing much happened after that. Once again, Hartwig could not imagine why the Canadian corvette failed to deliver an underwater attack. Tony German, later an RCN captain and then a junior officer on the bridge of Weyburn, later commented to Michael Hadley, “It is a fact that Weyburn didn’t get a sniff of him on asdic although we’d seen him twice, large as life.” While all this was happening, Hartwig’s latest brace of torpedoes found the little 1,781-ton Canadian steamer Donald Stewart and sent her to the bottom.

It was the RCAF and its constant air patrols that eventually made life in the Strait of Belle Isle unprofitable, and encouraged both Hartwig and Hoffmann to move south, into the choke point of trade along the Gaspé coast. They also forced Ruggeberg to head east along the north coast of Newfoundland towards Conception Bay. All three would find good hunting: the worst of the Battle of the St. Lawrence was yet to come.

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